People talk about Dirk's shot being unlockable and its about a foot lower in its release than Kareem's. Eaton could, on rare ocassion, block the 'later' sky hook he had no chance of catching the one that Chamberlain caught in that video. Kareem does a "Dream shake" (its actually a Rutger playground move made popular by the Pearl) in that video and was way too quick for most centers - that video you provided is in slow motion. Eaton could not have aligned his footing to be close to matching KAJ's quickness and torques. Kareem had way more bounce in his step when he first came into the league.

The later skyhook was slower, more methodical and much more predictable. As he got older it was a lazier shot with just more arch and shoulder space. When 6'5 Dantley had bounce in his step his release point was about at 7 feet and his shot was rarely blocked and he lived posting up. When he slowed down it was getting swatted. And you also didn't factor in that Kareem never scored like that ever again and that back then KAJ had to be more creative like the rest of the centers in that league at that time - No Magic with the hook up down low. The sky hook was a work in regress after that. You never see the footing get set as quick, and you never see the preliminary moves as fluid than in that Chamberlain film.

dirk's shot is unblockable because he creates so much separation. something we've never seen before by a 7ft guy.

IMO dirk shot is slightly more unblockable than kareem's because it is guarded by much smaller defenders, and dirk really creates absurd amount of spaces with his knee. ESPN sports science broke down the dirk fadeaway, and they said dirk creates 4ft of separation. and i remember host was saying even yao ming(9ft 8 standing reach) with derrick rose's 40 inch vertical can't block dirk's classic fadeaway. 9ft 8 + 40 inch = 13ft

but of course kareem's sky hook was more dominant because it was such a high % shot. at the end of the day, dirk is below .50% shooter.